The present invention is a process for the manufacture of turbine blades cooled by means of a porous body and product obtained by this process.
Cooled turbine blades presently in use employ sophisticated cast devices, such as the presence inside the hollow blades of picots, loops, fins, disturbers, etc. These internal organs of blades are produced by means of complicated and expensive ceramic cores, which must be dissolved after casting and which render the task of the founders delicate.
It is further possible to obtain satisfactory cooling of the blades by filling the cavity of hollow blades with a porous material which has the additional advantage of contributing to their mechanical strength by attenuating vibrations.
Experiments were effected with a material consisting of microspheres brazed by diffusion, but in such a material pressure losses are large and the circulation of the air requires very high pressures.
A porous material is known further, consisting of metal chips and being the object of U.S. application Ser. No. 58,487, filed July 18, 1979, said material having a porosity five to six times greater than that of the material made of spheres.